Muscle cramps can be excruciating. The muscle clenches relentlessly -- and even if it only lasts a few seconds, it feels like the worst pain you've ever had. Fortunately, they don't lead to serious injuries (although you might experience some muscle soreness the next day). Unfortunately, no one really knows what causes them or how to prevent them.
Many believe that dehydration leads to cramping, but that isn't really the case. Studies have shown that hydration isn't the underlying issue, although it might be an electrolyte imbalance, in which case drinking electrolytic sports drinks could help [source: Kolata]. It might be nerve misfiring due to muscle fatigue, which would be preventable by eating enough carbs. Some cramp sufferers have found relief with deep muscle massage.
There are some medical conditions that show up as muscle cramps, so if you have frequent cramps that you can't get rid of, you should see a doctor.